Pixel circuit, display panel and display apparatus

ABSTRACT

Provided is a pixel circuit, a display panel and a display apparatus. The pixel circuit comprises a pixel compensation module, a light emitting module and a touch detection module; the pixel compensation module comprises first to fifth switch units, a pixel driving unit and an energy storage unit; and the touch detection module comprises a detection sub-module and an output sub-module. In the pixel circuit provided by the present disclosure, a pixel compensation module and a touch detection module are integrated, and the pixel compensation module and the touch detection module share a data voltage and scan signal lines. As such, it is possible to reduce the number of signal lines, such that the pitch of pixels is dramatically reduced and IC cost is decreased, achieving higher pixel density. At the same time, in the pixel circuit provided by the present disclosure, the operating current flowing through the electroluminescent unit is not influenced by the threshold voltage of the corresponding driving transistor, and it is possible to avoid nonuniformity in brightness of display caused by threshold voltage drift of driving transistors.

TECHNICAL FIELD OF THE DISCLOSURE

The present disclosure relates to a pixel circuit, a display panel and adisplay apparatus.

BACKGROUND

With the rapid development of display technologies, display apparatuseswith touch function are becoming more and more popular due to theiradvantages such as visualized operation. According to different relativepositions of the touch screen panel relative to the display panel,existing display apparatuses with touch function can be generallyclassified into two categories, the on cell touch screen panel and thein cell touch screen panel. Compared with the on cell touch screenpanel, the in cell touch screen panel has smaller thickness and higherlight transmittance.

As for existing display apparatuses, the OLED (Organic Light EmittingDiode) as a current type light emitting device is more and more appliedto high performance display areas due to its characteristics such asself light emitting, fast response, wide angle of view and ability ofbeing fabricated on a flexible substrate. According to different drivingmanners, OLED display apparatuses can be classified into two categories,the PMOLED (Passive Matrix Driving OLED) and the AMOLED (Active MatrixDriving OLED). The AMOLED display is expected to become the nextgeneration new flat display in place of the LCD (Liquid Crystal Display)due to its advantages such as low fabrication cost, high response speed,low power consumption, DC driving applicable to portable devices, largeoperating temperature range. In existing AMOLED display panels, eachOLED is driven to emit light by a pixel driving circuit composed ofmultiple TFT (Thin Film Transistor) switches within one pixel unit onthe array substrate to realize display. The pixel driving circuitdirectly determines the quality of the light emitting display of theOLED. Therefore, the design of the pixel driving circuit is keytechnological content of the AMOLED. FIG. 1 is a schematic circuitstructure diagram of a normal pixel driving circuit. As shown in FIG. 1,the pixel driving circuit comprises a switch TFT T1, a driving TFT T2and a storage capacitor C, and T1 and T2 here are both P-channel drivingTFTs. A gate of T1 is connected to a scan line Scan[1], a source of T1is connected to a data voltage line Vdata, and a drain of T1 isconnected to terminal B of the capacitor C. Terminal A of C is connectedto a drain of T2. Terminal B of C is also connected to a gate of T2, asource of T2 is connected to an operating voltage Vdd, and a drain of T2is connected to a corresponding OLED. When Scan[1] scans to a row ofpixel circuit to be at a low voltage level, T1 is controlled to turn on,and the data voltage Vdd is written to terminal B. When the scan of thisrow is over, Scan[1] becomes a high voltage level, and T1 is turned off.The data voltage stored in C drives T2 to make it generate current todrive the OLED to ensure that the OLED keeps emitting light within thetime of one frame. The saturation current of T2 (i.e., the currentfollowing through the OLED) I_(OLED)=K(V_(GS)−V_(th))², where K is acurrent constant related to T2, V_(GS) is voltage of the gate relativeto the source of T2, and V_(th) is a threshold voltage of T2. It can beseen that I_(OLED) is related to the threshold voltage V_(th) of T2. Inaddition, due to fabrication process, device aging and so on, in such a2T1C pixel driving circuit, the threshold voltage V_(th) of the drivingTFTs at each pixel point would drift, that is, the threshold voltages ofthe driving TFTs at different pixel points are not uniform, which iseasy to make the current flowing through the OLED at each pixel pointvaries with V_(th), such that the display brightness of the displayscreen is not uniform, influencing the display effect of the wholepicture.

On the other hand, the in cell TSP (Touch Screen Panel) fabricates asensor for touch and a driving circuit in each pixel unit on the arraysubstrate by the array process as well. If the sensor and the drivingcircuit of TSP are superimposed in an AMOLED pixel unit, it is necessaryto add a certain number of driving circuit TFTs. Therefore, certainspace of the pixel unit needs to be occupied additionally, but the freespace in the pixel unit is limited. This dramatically limits thesimultaneous fabrication of the in cell touch screen panel circuit andthe AMOLED driving circuit.

SUMMARY

At least one embodiment of the present disclosure provides a pixelcircuit and a display apparatus to avoid the influence of a thresholddrift of a driving circuit on the display effect and improve theintegration level of an in cell touch screen panel circuit and a pixeldriving circuit.

At least one embodiment of the present disclosure provides a pixelcircuit comprising a pixel compensation module, a light emitting moduleand a touch detection module; wherein

the pixel compensation module comprises first to fifth switch units, apixel driving unit and an energy storage unit;

a first terminal of the first switch unit is connected to a firstoperating voltage, a second terminal of the first switch unit isconnected to an input terminal of the pixel driving unit, and a controlterminal of the first switch unit is connected to a first scan signalline;

a first terminal of the second switch unit is connected to a secondterminal of the energy storage unit, a second terminal of the secondswitch unit is grounded, a control terminal of the second switch unit isconnected to a third scan signal line;

a first terminal of the third switch unit is connected to a firstterminal of the energy storage unit, a second terminal of the thirdswitch unit is connected to a data voltage, a control terminal of thethird switch unit is connected to a fourth scan signal line;

a first terminal of the fourth switch unit is connected to an outputterminal of the pixel driving unit, a second terminal of the fourthswitch unit is connected to the second terminal of the energy storageunit, a control terminal of the fourth switch unit is connected to thefourth scan signal line;

a first terminal of the fifth switch unit is connected to the outputterminal of the pixel driving unit, a second terminal of the fifthswitch unit is connected to the light emitting module, a controlterminal of the fifth switch unit is connected to a second scan signalline;

a control terminal of the pixel driving unit is connected to the secondterminal of the energy storage unit; and

the touch detection module comprises a detection sub-module and anoutput sub-module, wherein the detection sub-module is connected to thethird scan signal line, a second operating voltage and the data voltagerespectively for detecting a touch signal, and the output sub-module isconnected to the fourth scan signal line, a touch signal read line andthe detection sub-module respectively for outputting a touch detectionsignal to the touch signal read line according to an input of the fourthscan signal line.

Optionally, the light emitting module comprises an electroluminescentelement, and the fifth switch unit is connected between the outputterminal of the pixel driving unit and an anode of theelectroluminescent element.

Optionally, the energy storage unit is a first capacitor.

Optionally, the output sub-module comprises a sixth switch unit whosefirst terminal is connected to the touch signal read line, whose secondterminal is connected to the detection sub-module, and whose controlterminal is connected to the fourth scan signal line.

Optionally, the detection sub-module comprises a seventh unit, a touchsignal driving unit, a second capacitor and a touch electrode, a firstterminal of the seventh switch unit is connected to the data voltage, asecond terminal of the seventh switch unit is connected to a controlterminal of the touch signal driving unit, a control terminal of theseventh switch unit is connected to the third scan signal line; an inputterminal of the touch signal driving unit is connected to the secondoperating voltage, an output terminal of the touch signal driving unitis connected to the sixth switch unit; the second capacitor is connectedbetween the input terminal and the control terminal of the touch signaldriving unit; the touch electrode is connected to the control terminalof the touch signal driving unit.

Optionally, the control terminal of the sixth switch unit is connectedto the second scan signal line instead of the fourth scan signal line.

Optionally, the control terminal of the seventh switch unit is connectedto the fourth scan signal line instead of the third scan signal line.

Optionally, the respective switch units and driving units are TFTs.

Optionally, each TFT is of P channel type; the control terminal of thedriving unit is a gate of a TFT, the input terminal of the driving unitis a source of the TFT, the output terminal of the driving unit is adrain of the TFT; the control terminal of each switch unit is a gate ofa TFT, the first terminal and the second terminal of each switch unitcorrespond to a source and a drain of the TFT respectively.

The present disclosure also provides a display panel comprising pixelcircuits according to any of the above.

Further, the pixel circuits are distributed periodically on the displaypanel.

The present disclosure also provides a display apparatus comprising adisplay panel according to any of the above.

According to the pixel circuit and the display apparatus provided by thepresent disclosure, a pixel compensation module and a touch detectionmodule are integrated in the pixel circuit, and the pixel compensationmodule and the touch detection module share a data voltage and scansignal lines. As such, it is possible to reduce the number of signallines, such that the pitch of pixels is dramatically reduced and IC costis decreased, achieving higher pixel density. At the same time, in thepixel circuit provided by the present disclosure, the operating currentflowing through the electroluminescent unit is not influenced by thethreshold voltage of the corresponding driving transistor, and it ispossible to avoid nonuniformity in brightness of display caused bythreshold voltage drift of driving transistors.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a circuit structure diagram of a normal pixel driving circuit;

FIGS. 2a-2c are schematic circuit structure diagrams of pixel circuitsprovided by embodiments of the present disclosure;

FIG. 3 is a time sequence diagram of key signals in a driving method fora pixel circuit shown in FIG. 2 a;

FIGS. 4a-4d are schematic diagrams of current directions and voltagevalues of a pixel circuit shown in FIG. 2a under different timesequences;

FIG. 5 is a schematic diagram of potential change of the pixel electrodein a pixel circuit provided by the present disclosure;

FIG. 6 is a schematic diagram of positional relation between pixelcircuits and pixels in a display panel provided by an embodiment of thepresent disclosure.

DETAILED DESCRIPTION

In the following, specific implementations of the present disclosure arefurther described in connection with figures and embodiments. Thefollowing embodiments are only for more clearly illustrating thetechnical solutions of the present disclosure, but not for limiting theprotection scope of the present disclosure. In the figures, the samereference symbols represent the same elements.

FIGS. 2a-2c are schematic circuit structure diagrams of pixel circuitsprovided by embodiments of the present disclosure. As shown in FIG. 2a ,the pixel circuit comprises:

a pixel compensation module 100, a light emitting module 200 and a touchdetection module.

The pixel compensation module 100 comprises a first switch unit T1, asecond switch unit T2, a third switch unit T3, a fourth switch unit T4,a fifth switch unit T5, a pixel driving unit DT1, and an energy storageunit C1.

A first terminal of the first switch unit T1 is connected to a firstoperating voltage Vdd, a second terminal of the first switch unit T1 isconnected to an input terminal of the pixel driving unit DT1, and acontrol terminal of the first switch unit T1 is connected to a firstscan signal line Em.

A first terminal of the second switch unit T2 is connected to a secondterminal b of the energy storage unit C1, a second terminal of thesecond switch unit T2 is grounded, a control terminal of the secondswitch unit T2 is connected to a third scan signal line Scan[2].

A first terminal of the third switch unit T3 is connected to a firstterminal a of the energy storage unit C1, a second terminal of the thirdswitch unit T3 is connected to a data voltage Vdata, a control terminalof the third switch unit T3 is connected to a fourth scan signal lineScan[3].

A first terminal of the fourth switch unit T4 is connected to an outputterminal of the pixel driving unit DT1, a second terminal of the fourthswitch unit T4 is connected to the second terminal b of the energystorage unit C1, a control terminal of the fourth switch unit T4 isconnected to the fourth scan signal line Scan[3].

A first terminal of the fifth switch unit T5 is connected to the outputterminal of the pixel driving unit DT1, a second terminal of the fifthswitch unit T5 is connected to the light emitting module 200, a controlterminal of the fifth switch unit T5 is connected to a second scansignal line Scan[1].

A control terminal of the pixel driving unit DT1 is connected to thesecond terminal b of the energy storage unit C1.

The touch detection module comprises a detection sub-module 310 and anoutput sub-module 320, wherein the detection sub-module 310 is connectedto the third scan signal line Scan[2], a second operating voltage Vintand the data voltage Vdata respectively for detecting a touch signal,and the output sub-module 320 is connected to the fourth scan signalline Scan[3], a touch signal read line Y-read Line and the detectionsub-module 310 respectively for outputting a touch detection signal tothe Y-read Line according to an input of Scan[3].

According to the pixel circuit provided in the present disclosure, apixel compensation module and a touch detection module are integrated inthe pixel circuit, and the pixel compensation module and the touchdetection module share a data voltage and scan signal lines. As such, itis possible to reduce the number of signal lines, such that the pitch ofpixels is dramatically reduced and IC cost is decreased, achievinghigher pixel density. At the same time, the operating current flowingthrough the electroluminescent unit is not influenced by the thresholdvoltage of the corresponding driving transistor, solving thenonuniformity in brightness of display caused by threshold voltage driftof driving transistors.

Here, the second operating voltage Vint is used to provide drivingpulses.

For example, the light emitting module 200 can comprise anelectroluminescent element whose anode is connected to the outputterminal of the pixel driving unit DT1 in the pixel compensation moduleand whose cathode is grounded.

In embodiments of the present disclosure, the electroluminescent elementcan be various normal current driving light emitting devices includingLED (Light Emitting Diode) or OLED (Organic Light Emitting Diode). Inembodiments of the present disclosure, OLED is taken as an example fordescription.

Further, the energy storage unit C1 is a capacitor (referred to as firstcapacitor). However, in practical applications, the energy storage unitcan adopt other elements with energy storage function according todesign needs.

Further, as shown in FIG. 2a , the pixel driving unit DT1 is a drivingamplification switch.

Further, as shown in FIG. 2a , the output sub-module 320 comprises asixth switch unit T6 whose first terminal is connected to the touchsignal read line Y-read Line, whose second terminal is connected to thedetection sub-module 310, and whose control terminal is connected toScan[3].

Further, the detection sub-module 310 comprises a seventh unit T7, atouch signal driving unit DT2, a second capacitor C2 and a touchelectrode d. A first terminal of the seventh switch unit T7 is connectedto the data voltage Vdata, a second terminal of the seventh switch unitT7 is connected to a control terminal of the touch signal driving unitDT2, a control terminal of the seventh switch unit T7 is connected tothe third scan signal line Scan[2]; an input terminal of the touchsignal driving unit DT2 is connected to the second operating voltageVint, an output terminal of the touch signal driving unit DT2 isconnected to one terminal of the sixth switch unit T6; the secondcapacitor C2 is connected between the input terminal and the controlterminal of the touch signal driving unit DT2; the touch electrode d isconnected to the control terminal of the touch signal driving unit DT2.At the same time, since the control terminal of DT2 is also connected toone terminal of C2, the touch electrode d is also connected to thecapacitor C2 which functions to maintain the voltage of the touchelectrode d.

Further, as shown in FIG. 2b , Scan[3] connected to the control terminalof the output sub-module 320 can be replaced by Scan[1], that is, thecontrol terminal of T6 is connected to Scan[1] instead of Scan[3].

Further, on the basis of the circuit shown in FIG. 2b , as shown in FIG.2c , Scan[2] connected to the control terminal of the detectionsub-module 310 can be replaced by Scan[3], that is, the control terminalof T7 is connected to Scan[3] instead of Scan[2].

Further, respective switch units and driving units are TFTs.

Further, as shown in FIG. 2a-2c , each TFT is of P channel type. Now,the input terminal of the driving unit is a source of a TFT, the outputterminal of the driving unit is a drain of the TFT and the controlterminal of the driving unit is a gate of the TFT. For each switch unit,the control terminal is also a gate of a TFT, and the first terminal andthe second terminal correspond to a source and a drain of the TFTrespectively.

Using the same type of transistors can realize unification of processprocedures so as to improve the yield of the products. It can beunderstood by those skilled in the art that the types of the transistorscan be not completely the same in practical applications. For example,T2 and T7 can be N channel type transistors, and T3 and T4 can be Pchannel type transistors. As long as two switch units whose controlterminals are connected to the same scan signal line can have the sameON/OFF state, the technical solutions provided in the presentapplication can be realized. The implementations described in thepresent disclosure should not be understood as limiting of theprotection scope of the present disclosure.

Next, the operating principles of the pixel circuit in FIG. 2a will bedescribed in connection with FIG. 3 and FIG. 4. In order to facilitatethe description, it is assumed that respective switch units and drivingunits are P channel TFTs, and the energy storage unit is a capacitor.FIG. 3 is a possible time sequence diagram of scan signals on respectivescan signal lines and the data voltage Vdata within one frame when thepixel circuit shown in FIG. 2a operates, which can be divided into fourphases, as shown in FIG. 3, comprising a first phase W1 (the phase inwhich the pixel compensation module resets and the touch detectionmodule resets), a second phase W2 (the phase in which the pixelcompensation module charges and the touch detection module detects), athird phase W3 (the phase in which the pixel compensation module jumpsand the touch detection module halts), and a fourth phase W4 (the phasein which the pixel compensation module emits light and the touchdetection module halts). FIGS. 4a-4d are schematic diagrams of currentdirections and voltage values of the pixel circuit shown in FIG. 2aunder different time sequences. In the above respective phases W1-W4,the current directions and the voltage values of the pixel circuit areas shown respectively in FIG. 4a , FIG. 4b , FIG. 4c and FIG. 4 d.

In the first phase W1, referring to FIG. 3, Scan[2] at this time is at alow voltage level, other scan signal lines are at high voltage levels,and the data voltage Vdata is applied with a first voltage Vp. Referringto FIG. 4a , in the pixel compensation module 100, only T2 is turned on,now point b is reset to be grounded, and the potential of the point b is0 V, which resets the voltage signal of the last frame in the capacitorC1. In the touch detection module, T7 is turned on, and T6 and DT2 areturned off, realizing the reset of the touch detection module. Afterreset, the potential at d is Vp. As can be seen, Scan[2] is equivalentto the reset scan signal line Reset line of the pixel compensationmodule 100 and the touch detection module.

In the second phase W2, referring to FIG. 3, now Em and Scan[1] are atlow voltage levels, other scan signal lines are at high voltage levels,and the voltage Vp of Vdata remains unchanged. Referring to FIG. 4b , inthe pixel compensation module, T1, T3 and T4 are turned on, and T2 andT5 are turned off. Since point b is grounded before, the pixel drivingunit DT1 is turned on, and Vdd charges point b through T1→DT1→T4 untilpoint b is charged to Vdd−Vth1 (the potential difference between thegate and the source of DT1 is Vth1, and Vth1 is the threshold voltage ofDT1). At the same time, since T3 is turned on, Vdata charges point a ofC1 through T3, and the voltage level of point a remains Vp after thecharging is finished. Since the turning off of T5 makes the current notflow through OLED, the life loss of OLED is indirectly reduced.

In the touch detection module, referring to FIG. 4b , T7 is turned off,and T6 is turned on. FIG. 5 is a schematic diagram of potential changeof the pixel electrode in the pixel circuit provided in the presentdisclosure. In the second phase W2, as shown in FIG. 5, when a fingertouches, referring to the dashed line part of the figure, the potentialVd of the touch electrode d decreases (for example decreases by Vf),directly causing the gate potential of DT2 to decrease to reach theturning-on condition of DT2. Now, Vint inputs an electrical signal toY-read line through DT2 and T6. After the finger touch causes Vd todirectly decrease by Vf, Vd decreases continuously to 0 due to thedischarge of the capacitor C2. However, if there is no finger touch atthis time, referring to the solid line part, the potential Vd of thetouch electrode d will not decrease, but still remains at Vp. Now, DT2is turned off, and no electrical signal can be detected in Y-read line.

Now, if a finger touches, the potential of the touch electrode d will bedirectly caused to decrease, and the turning-on condition of DT2 isreached. At this point, the I&V characteristic curve is in theamplification region, DT2 as an amplification TFT will turn on andamplify the signal of coupling pulses, and Y-Read Line collects thesignal in the Y direction. Scan[3] as the scan signal in the X direction(row direction) also has the collection function (since the signal inthe Y direction can be collected only when Scan[3] is at a low voltagelevel, and Scan[3] in pixels of a specific row is a low voltage levelsignal at a specific time; as such, it is possible to determine whichrow Scan[3] has scanned according to the time of the collected touchsignal to further determine the coordinates of X). In such a way, the X,Y coordinates of the finger touch position are determined Such aprocedure only needs a finger to perform touch, and the coordinateposition can be collected any time.

It can be seen that, in an embodiment of the present disclosure, Scan[3]functions as the X direction touch signal read line X-read line.

In the third phase W3, as shown in FIG. 3, only Scan[3] is at a lowvoltage level, other scan signal lines are at high voltage levels, andthe voltage applied in Vdata is raised to Vp+ΔV. As shown in FIG. 4c ,in the pixel compensation module 100, now T3 and T4 are turned on, andother TFTs are turned off. Now, the potential at point a changes fromoriginal Vp to Vp+ΔV, but point b is at a floating state. Therefore, inorder to remain the original potential difference (Vdd−Vth1−Vp) betweenpoint a and point b, the potential at point b of the gate of DT1 wouldjump by the same voltage level. The potential at point b jumps to andremains at Vdd−Vth1+ΔV to prepare for the next phase.

In the touch detection module, except T6, other devices do not operate.The touch detection module is in a halt state. In such a way, it ispossible to reduce the influence on the display procedure.

In the fourth phase W4, as shown in FIG. 3, only Scan[1] and Em are atlow voltage levels, and other scan signal lines are at high voltagelevels. As shown in FIG. 4d , in the pixel compensation module 100, nowT1 and T5 are turned on, and T2, T3 and T4 are turned off. Vdd makesOLED start to emit light through T1→DT1→T5.

In the touch detection module, all TFTs are turned off, and the touchdetection module is at a halt state, so as to reduce the effect on thedisplay procedure.

Therefore, according to the current characteristic of TFT in thesaturation region, it is possible to obtain the current flowing throughthe pixel driving unit DT1 as:

I _(OLED) =K(Vgs−Vth1)² =K[Vdd−(Vdd−Vth1+ΔV)−Vth1]² =K(ΔV)²,

It can be seen from the above equation that the operating currentI_(OLED) is not affected by Vth1 now, but only related to ΔV, whichsolves the problem of threshold voltage drift of the driving TFTs causedby the fabrication process and long time operation, eliminates itsinfluence on I_(OLED), and ensures normal operation of OLED.

The operating principle of the pixel circuits provided in FIG. 2b andFIG. 2c is almost the same as that of the pixel circuit in FIG. 2a . Thedifference is only that, in the pixel circuit as shown in FIG. 2b orFIG. 2c , the touch signal can only be detected when Scan[1] is at a lowvoltage level (that is, in the fourth phase W4), and now Scan[1] isequivalent to X-read line; in addition, in the pixel circuit as shown inFIG. 2c , the touch detection module can only be reset when Scan[3] isat a low voltage level, and now Scan[3] instead of Scan[2] functions asReset line.

The present disclosure also provides a display panel comprising any ofthe above pixel circuits.

Alternatively, the pixel circuits are distributed periodically on thedisplay panel. In practical applications, it is not necessary for allthe positions corresponding to respective pixels to each adopt the pixelcircuit provided by embodiments of the present disclosure (for example,among three pixels, one is provided with the pixel circuit provided byembodiments of the present disclosure, and the other pixels are providedwith normal pixel circuits) to realize the detection of the touchsignal. As shown in FIG. 6, one pixel circuit (PU) provided byembodiments of the present disclosure is arranged every three pixels.

The present disclosure also provides a display apparatus comprising theabove display panel.

The display apparatus here can be any product or means with displayfunction such as an electronic paper, a cell phone, a tablet, a TV set,a display, a notebook computer, a digital photo frame, a navigator andso on.

The above descriptions are only alternative implementations of thepresent disclosure. It should be noted that those skilled in the art canmake various variations and improvements without departing from thetechnical principle of the present disclosure. These variations andimprovements are also intended to be incorporated within the protectionscope of the present disclosure.

The present application claims the priority of Chinese PatentApplication No. 201410302898.8 filed on Jun. 27, 2014, entire content ofwhich is incorporated as part of the present invention by reference.

1. A pixel circuit comprising a pixel compensation module, a lightemitting module and a touch detection module; wherein the pixelcompensation module comprises first to fifth switch units, a pixeldriving unit and an energy storage unit; a first terminal of the firstswitch unit is connected to a first operating voltage, a second terminalof the first switch unit is connected to an input terminal of the pixeldriving unit, and a control terminal of the first switch unit isconnected to a first scan signal line; a first terminal of the secondswitch unit is connected to a second terminal of the energy storageunit, a second terminal of the second switch unit is grounded, a controlterminal of the second switch unit is connected to a third scan signalline; a first terminal of the third switch unit is connected to a firstterminal of the energy storage unit, a second terminal of the thirdswitch unit is connected to a data voltage, a control terminal of thethird switch unit is connected to a fourth scan signal line; a firstterminal of the fourth switch unit is connected to an output terminal ofthe pixel driving unit, a second terminal of the fourth switch unit isconnected to the second terminal of the energy storage unit, a controlterminal of the fourth switch unit is connected to the fourth scansignal line; a first terminal of the fifth switch unit is connected tothe output terminal of the pixel driving unit, a second terminal of thefifth switch unit is connected to the light emitting module, a controlterminal of the fifth switch unit is connected to a second scan signalline; a control terminal of the pixel driving unit is connected to thesecond terminal of the energy storage unit; and the touch detectionmodule comprises a detection sub-module and an output sub-module,wherein the detection sub-module is connected to the third scan signalline, a second operating voltage and the data voltage respectively fordetecting a touch signal, and the output sub-module is connected to thefourth scan signal line, a touch signal read line and the detectionsub-module respectively for outputting a touch detection signal to thetouch signal read line according to an input of the fourth scan signalline.
 2. The pixel circuit according to claim 1, wherein the lightemitting module comprises an electroluminescent element, and the fifthswitch unit is connected between the output terminal of the pixeldriving unit and an anode of the electroluminescent element.
 3. Thepixel circuit according to claim 1, wherein the energy storage unit is afirst capacitor.
 4. The pixel circuit according to claim 1, wherein theoutput sub-module comprises a sixth switch unit whose first terminal isconnected to the touch signal read line, whose second terminal isconnected to the detection sub-module, and whose control terminal isconnected to the fourth scan signal line.
 5. The pixel circuit accordingto claim 1, wherein the detection sub-module comprises a seventh unit, atouch signal driving unit, a second capacitor and a touch electrode, afirst terminal of the seventh switch unit is connected to the datavoltage, a second terminal of the seventh switch unit is connected to acontrol terminal of the touch signal driving unit, a control terminal ofthe seventh switch unit is connected to the third scan signal line; aninput terminal of the touch signal driving unit is connected to thesecond operating voltage, an output terminal of the touch signal drivingunit is connected to the sixth switch unit; the second capacitor isconnected between the input terminal and the control terminal of thetouch signal driving unit; the touch electrode is connected to thecontrol terminal of the touch signal driving unit.
 6. The pixel circuitaccording to claim 4, wherein the control terminal of the sixth switchunit is connected to the second scan signal line instead of the fourthscan signal line.
 7. The pixel circuit according to claim 6, wherein thecontrol terminal of the seventh switch unit is connected to the fourthscan signal line instead of the third scan signal line.
 8. The pixelcircuit according to claim 1, wherein the respective switch units anddriving units are TFTs.
 9. The pixel circuit according to claim 8,wherein each TFT is of P channel type; the control terminal of thedriving unit is a gate of a TFT, the input terminal of the driving unitis a source of the TFT, the output terminal of the driving unit is adrain of the TFT; the control terminal of each switch unit is a gate ofa TFT, the first terminal and the second terminal of each switch unitcorrespond to a source and a drain of the TFT respectively.
 10. Adisplay panel comprising pixel circuits according to claim
 1. 11. Thedisplay panel according to claim 10, wherein the pixel circuits aredistributed periodically on the display panel.
 12. A display apparatuscomprising a display panel according to claim
 10. 13. The pixel circuitaccording to claim 2, wherein the energy storage unit is a firstcapacitor.
 14. The pixel circuit claim 2, wherein the output sub-modulecomprises a sixth switch unit whose first terminal is connected to thetouch signal read line, whose second terminal is connected to thedetection sub-module, and whose control terminal is connected to thefourth scan signal line.
 15. The pixel circuit claim 3, wherein theoutput sub-module comprises a sixth switch unit whose first terminal isconnected to the touch signal read line, whose second terminal isconnected to the detection sub-module, and whose control terminal isconnected to the fourth scan signal line.
 16. The pixel circuit claim13, wherein the output sub-module comprises a sixth switch unit whosefirst terminal is connected to the touch signal read line, whose secondterminal is connected to the detection sub-module, and whose controlterminal is connected to the fourth scan signal line.
 17. The pixelcircuit according to claim 2, wherein the detection sub-module comprisesa seventh unit, a touch signal driving unit, a second capacitor and atouch electrode, a first terminal of the seventh switch unit isconnected to the data voltage, a second terminal of the seventh switchunit is connected to a control terminal of the touch signal drivingunit, a control terminal of the seventh switch unit is connected to thethird scan signal line; an input terminal of the touch signal drivingunit is connected to the second operating voltage, an output terminal ofthe touch signal driving unit is connected to the sixth switch unit; thesecond capacitor is connected between the input terminal and the controlterminal of the touch signal driving unit; the touch electrode isconnected to the control terminal of the touch signal driving unit. 18.The pixel circuit according to claim 3, wherein the detection sub-modulecomprises a seventh unit, a touch signal driving unit, a secondcapacitor and a touch electrode, a first terminal of the seventh switchunit is connected to the data voltage, a second terminal of the seventhswitch unit is connected to a control terminal of the touch signaldriving unit, a control terminal of the seventh switch unit is connectedto the third scan signal line; an input terminal of the touch signaldriving unit is connected to the second operating voltage, an outputterminal of the touch signal driving unit is connected to the sixthswitch unit; the second capacitor is connected between the inputterminal and the control terminal of the touch signal driving unit; thetouch electrode is connected to the control terminal of the touch signaldriving unit.
 19. The pixel circuit according to claim 4, wherein thedetection sub-module comprises a seventh unit, a touch signal drivingunit, a second capacitor and a touch electrode, a first terminal of theseventh switch unit is connected to the data voltage, a second terminalof the seventh switch unit is connected to a control terminal of thetouch signal driving unit, a control terminal of the seventh switch unitis connected to the third scan signal line; an input terminal of thetouch signal driving unit is connected to the second operating voltage,an output terminal of the touch signal driving unit is connected to thesixth switch unit; the second capacitor is connected between the inputterminal and the control terminal of the touch signal driving unit; thetouch electrode is connected to the control terminal of the touch signaldriving unit.
 20. The pixel circuit according to claim 13, wherein thedetection sub-module comprises a seventh unit, a touch signal drivingunit, a second capacitor and a touch electrode, a first terminal of theseventh switch unit is connected to the data voltage, a second terminalof the seventh switch unit is connected to a control terminal of thetouch signal driving unit, a control terminal of the seventh switch unitis connected to the third scan signal line; an input terminal of thetouch signal driving unit is connected to the second operating voltage,an output terminal of the touch signal driving unit is connected to thesixth switch unit; the second capacitor is connected between the inputterminal and the control terminal of the touch signal driving unit; thetouch electrode is connected to the control terminal of the touch signaldriving unit.